The use of omnidirectional vision navigation systems for providing video or visual image information useful in robot navigation, or for the location of mobile systems, is known in the art. For example, Zhongfei Zhang, Richard Weiss, and Edward M. Riseman, presented a paper on Apr. 3, 1991, entitled "Segment-Based Matching for Visual Navigation", Computer Information Science Department, University of Massachusetts, Amherst, Mass., "COINS PR91-35". The paper teaches the use of a reflecting globe or spherical mirror, mounted on top of a mobile robot above a camera. The camera converts the picture received to a 360.degree. video image of the surrounding environment. The video image from the camera is processed for obtaining a fixed set of target locations for permitting a robot to navigate between desired locations by carrying out a sequence of homing tasks relative to the target locations. The 360.degree. view taken at a given time is condensed into a 1-dimensional location signature. Correlation techniques are used for providing matching between location signatures in navigating the robot. The location signature represented by three types of segments identified as increasing, decreasing, and constant, respectively. In the system, a "horizon circle" is superimposed upon the 360.degree. image for taking a sample of the image every degree. The "horizon circle" forms a circle band composed of 360 ticks. The circle is designated as being the actual horizon circle, with each tick being a sample thereof, as a function of the azimuth orientation. The resultant sequences of linear segments obtained are not all used for matching, whereby selective ones are obtained for providing "characteristic features" for matching between images, and navigating a robot to move from one image location to a next, in a successive manner. Each 360.degree. video image is processed using a spherical coordinate system centered upon the origin of the image plane. The "characteristic features" chosen for matching are those which appear to be most distinctive and reliable for such use, for example parts of the processed waveform having a large slope for feature transition.
Another paper by Sung Jun Oh and Ernest L. Hall, entitled "A Study of the Characteristics of a Omnidirectional Vision Sensor", published in SPIE, Volume 804 of Advances and Image Processing in 1987, on pages 259 through 267. The detector of the system includes a fish eye lens mounted over a video camera, for projecting a 360.degree. image of its surroundings. The video camera consists of a CCD or charge couple device camera for providing a video signal representative of the 360.degree. image to an image processing system.
Another known system for providing route recognition in robot navigation includes the use of a rotating slit in combination with a video camera for providing a video image band representative of a panoramic view of the environment a robot is to navigate. As the rotating slit camera apparatus is moved linearly the panoramic view changes. Successive 2D panoramic image strips are connected together for providing a continuous panoramic view relative to a robot moving through the chosen environment. The images are processed through use of circular dynamic programming to obtain vertical line segments from the images for use in matching techniques for guiding the robot's movement. The robot's signal processor compares its present panoramic view with recorded panoramic views in order to determine the robot's heading, and correct the same if it is off course. See J. Y. Zheng and S. Tsuji, "Panoramic Representation for Route Recognition by a Mobile Robot", International Journal of Computer Vision, Volume 9:1, pages 55-76 (1992), Kluwer Academic Publishers, The Netherlands.
Present research for obtaining video information useful in route recognition for robot navigation, and for vehicle locator systems, is centered upon simplifying such systems while retaining reliable pattern matching. It is important that the amount of video image data necessary for reliable pattern matching be reduced to a minimum in order to reduce the size of the computer memories required by the associated systems.